The past weekend was a wet one:
Fortunately I’ve got a bike for that:

Yes, it does have a disgraceful fenderline:

But while they may look like a pair of poorly drawn eyebrows…

…they are no less effective for it. They’ve also been on and off multiple bikes at this point, having started life a decade and a half ago on the Scattante:

And by now they’re so bent and filthy I see no point going through all the trouble of trimming the stays and all that stuff simply to appease the fastidious among you. In fact, putting fenders on at all is one of the most tedious processes in all of cycledom–one of those things you’re always sure will just take you 20 minutes but somehow ends up taking at least two hours, like picking up something from Ikea. So once they’re on and not rubbing anything it’s very difficult to want to fine tune them. In fact it’s such a hassle I dismantled this entire bike, had the frame repainted, and completely reassembled it, and even then I still couldn’t be bothered to align the fenders:

[The Milwaukee pre-makeover.]
All of this is to say that if I owned a bike shop I’d charge $1,000 per wheel for the job and if you didn’t like it I’d tell you exactly where you could stick ’em. (That sounds harsh, but installing a fender into yourself is only marginally more painful than installing one on a bicycle.)
And for the record, I can do a decent job installing a pair of fenders when it actually matters-, such as when it’s my wife’s bike and not mine:

But even then, when I do it’s absolutely nothing like this video:
For one thing, instead of groovy music there’s just the sound of me cursing. For another, the very first thing he does is this:

Whereas my approach is to install everything, discover that the handlebars won’t turn, and only then do I remove the front fender again in order to bend the tab, at which point I remember that this happens EVERY SINGLE GODDAMN TIME.
But once they’re on it’s all worth it. Riding a bike on a wet road without fenders is like straddling someone’s face while they spritz you from below with a water bottle. And while I do appreciate that some people might enjoy that and in certain cases even pay good money for it (and no, that’s not a dig at anybody who works as a crotch-spritzer, sex work is real work after all), I prefer to keep road spray to a minimum.
Yet even I, a fender apologist, do find that once a bike is befendered I ride it less in dry conditions than I did previously. But why should this be? Well, one reason is that it reduces the bike’s off-roadability. In fact, I was once riding the Milwaukee offroad with fenders, a stick got lodged in the front one, and I went over the bars and broke my thumb–though it should be noted that was a different pair of fenders without safety tabs:

[Most plastic fenders seem to come with them these days, but if yours didn’t you can add them.]
But another reason I suppose is that subconsciously I think a road bike with fenders is somehow “slower,” and that it is compromised in some way that is not justified when there is no water to deflect, in the same way one might avoid riding a full suspension bike entirely on the road. But after riding the Milwaukee all weekend long, even long after the roads had dried out, I was reminded of how silly this is. The Milwaukee is my longest-serving bicycle and we are perfectly attuned; so not only did it feel fast, but it felt especially fast. Certainly part of that may be the Absence-Makes-The-Heart-Grow-Fonder Effect, but no less a personage than Jan Heine The Science Guy confirms that fenders do not slow you down:

In fact, the front part of the fender even speeds you up (though I guess the back part of the fender cancels that out):

Now I have no idea if any of this applies to my own wonky installation, but the bike was certainly zipping along, so I wonder if perhaps I’ve accidentally hit upon some sort of cutting-edge fenderline that acts to enhance the bicycle’s aerodynamic properties. Also, the fenders I’m using don’t have mud flaps, which add drag. I know you’re supposed to use mud flaps since it’s considerate to the riders behind you, but there are few things I care less about than the riders behind me.
Also, I’m slow, so any riders behind me will not be there for very long.
And finally, I should address the term “fenders” versus its transatlantic counterpart “mudguards,” which like most cycling Britishisms is silly and wrong. See, a fender fends off moisture, whereas you wouldn’t even want a fender on a muddy ride because it would get packed full of mud almost immediately. It’s almost as annoying a term as “mech,” which I really can’t stand because I always read it with the guttural throat-clearing “ch” the Internet tells me is called the “voiceless uvular fricative,” like the way an actual German person or a pretentious English-speaking person would pronounce the name Johann Sebastian Bacccccchhhhhhh.” But for sheer pomposity nothing rivals the term “seat pillar,” which…come on:

Hey, where’s the dropper pillar?